- IBM switch Users and Maintenance Guide

connect more than two hosts to the fibre channel storage server through switches.
The illustrations in the following sections show common host system configurations.
Note: The default configuration is one partition. Four-partition, eight-partition, and
sixteen-partition configuration upgrades are available as upgrade options.
You must perform partition upgrades one increment at a time, which means
you cannot upgrade directly from a four-partition configuration to a
sixteen-partition configuration; in this case, you would have to upgrade from
a four-partition configuration to an eight-partition configuration, and then from
the eight-partition configuration to a sixteen-partition configuration. Contact
your IBM reseller or marketing representative for more information.
Redundant host and drive loops
This section provides examples of DS4100 host fibre channel configurations.
DS4100 base storage server configurations: This section provides the following
examples of DS4100 base storage server host fibre channel configurations.
v Redundant host and drive fibre channel loop configurations, as shown in
Figure 25 on page 38
v Single SAN fabric configuration, as shown in Figure 26 on page 39
v Dual SAN fabric configuration, with an additional DS4100 and a DS4000 EXP100
attached, as shown in Figure 27 on page 39
v Two clusters, as shown in Figure 28 on page 40
Note:
These configurations have host and drive path failover protection and are
recommended for high availability.
Chapter 2. Installing the storage server 37